Tiltable band saw machine



July 7, 1953 D. ABRAHAM y A y 2,644,491

' TILTABLE vBAND sAw MACHINE Y Filed Feb. 1o, 1951 4 5 sheets-sheet 1 4Y INVENToR .27A wo ABRAHAM July 7, 1953 D. ABRAHAM l TILTABLE BAND .sAwMACHINE Filed Feb. 10, 151

. 3 Sheets- Sheet 2 INVENTOR 27A wo Aam/MM BY ATTORNEYS July 7, l1953 D.ABRAHAM 2,644,491

' TILTABLE BAND `sAw MACHINE FiledvFeb. 10, 1951 3 Sheets-Sheet 5lNvENToR l A wa ABRAHAM BY a/a' g ATTORNE s Patented .uy 7, 19.53

Hampden Brass and Aluminum Company, Springlield, Mass.,ra corporation ofMassachusetts y Application February 1o, 1951, serial No. 210,361

11 Claims.

This invention relates lto a band-saw machine having means forselectively changing the angle between the saw blade and the work table.

Such change of angular relationship between the saw blade and tablelisdesirable for cutting bevels and other purposes. In machines commonlyin use this change of angle is effected by changing the angle of thetable relative to the saw blade, the latter traveling in a fixed path.

, More satisfactory results from the standpoint 'of accuracy and ease inholding the work on the table are secured if the work table is heldhorizontal and the saw blade is tilted relative to the table. Variousstructures have been proposed which operate in the latter manner butsuch structures have proved unsatisfactory because of vthe complicatedmechanisms involved-Vin their operation and the excessive costs ofmanufacture 'and maintenance.

The principal object of the invention is to provide a band-saw in whichthe blade may be yeasily and rapidly -adjusted through large as well assmall angles relative to the table, the latter being maintainedsubstantially horizontal, and

which may be so adjusted while the blade is in motion with Ia minimum ofeffort andv attention from the'operator.

It is a further object to provide such amafdchine which is light, simpleand inexpensive to V*construct and maintain.

Broadly stated, the general and specic objects of the invention aresecured by providing means to impart a planetary motion to the table, asit fis moved with the saw and its-frame about the 'axis of the pivotalconnection of the saw frame to its support.

These as well as other and more particular objects relating to detailsof construction will be made clear in the following description, theaccompanying drawings, and in the claims.

In the drawings:

' Fig. 1 is a side elevation of a band-saw machine embodying theinvention;

Fig. 2 is a view looking from the right of Fig. t l, parts being brokenaway;

Fig. 3 is a View similar to Fig. 1 showing the saw blade tilted; K

' Fig. 4 is a View on an enlarged scale taken from the'right-hand sidebelow the table of Fig. 1 to show details of construction;

` Fig. 5 is a fragmentary side elevational View on a larger scaleshowing the pivotal mounting of the table, parts being broken away;

Fig. 6 is a view on line 6 6 of Fig. 5;

Fig.l 'l is an enlarged detail of the clamp be- Y 2 tween the tiltingframe and the base of the machine; and

. Fig. 8 is a diagrammatic view of an alternative arrangement.

The band-saw machine includes a fixed base- I pivotallysupporting, bymeans of a sleeve indi-V cated at 2, a C-frame 3, having upper'and lowerarms 4 and 5 respectively. Spaced upper and lower band wheels 6 arerotatably supportedin a common plane, which is also the plane in which lthe frame 3 pivots, on the upper arm 4 of the C-frame and on the base,respectively. `A flexible band-saw blade 'I is tensioned about thewheels 6 on frictional wheel rims Ii. A resilient wheel adjustingdevice, generally indicated at 9, of any suitable conventional type, isprovided von the upper arm 4 of the C-frame to move the upper Wheel Itoward and away from the lower wheel for adjustment of the tension ofthe blade 'I as desired.

A post I'l is adjustable vertically on the upper frame arm 4, being heldthereon by ayoke and screw device indicated generally at I2.v The post lI carries, kat its lowermost end portion, an upper saw blade guide I3and an upper bladeybearing I4 which may be of usual construction. Lowerguide I5 and bearing I6 are mounted on the lowerarm 5 of the .C-frame asis shown most Aclearly, in Figs. 5 and 6. Guide I5 (guide I3 isidentical) includes a pair of arms I'I atthe sides of thesaW blade'I,with guide pins I8 adjustable toward and awaykfrom the blade. Thebearing IB (bearing llli is identical) is provided with a rotatable`disc against vwhich the running blade 'I may bear' as a piece of workis pressed against thesaw edge of the blade.

The lower Wheel G is fixed on a shaft l which -is rotatably'supported inbearings at 2B in the y(not shown). A cover 22 supported and spaced fromthe C-frame by studs 23 is provided to encase the wheels 6 and most ofthe blade l.

The lowermost portion of the lower frame arm 5 is bifurcated to form twospaced lugs 2li (Figs.

2 and 4) which embrace a head 25 at theupperportion of base I. The head25 is in the form of a split clamp which is integral with base l andwhich secures the sleeve 2 to the base. The

` ends of sleeve 2 extend through openings in the lugs 24 and the sleeveforms the pivot about which the frame 3 tilts.`

Extending upwardly and forwardly from the head 25 and integral therewithare a pair of spaced ears 26 which lie inside the lugs 24 (Fig. 4). Asmall pivot block 27 is pivotally mounted between ears 26 by means ofpins 28, and the block is provided with an internally threaded apertureextending between the pins 28 and at right angles thereto. The innermostend of a jack screw 29 is threaded into the aperture, with the outermostend of the screw extending forwardly of the machine and carrying a handwheel 30.

The screw is supported at its outer end in a pivot block 3l which ispivoted to the upper end of a link 32, the lower end of which is pivotedat 33 to the base I. The screw is rotatably mounted in block 3 I, but isheld against longitudinal movement relative thereto.

The free end of arm is formed with an arcuate cradle 34 in which anarcuate plate 35 is secured by a machine screw 36. As best shown in Fig.6 the edges of theplate 35 extend outwardly of the sides of the cradleand engage in arcuate grooves 3l formed in the adjacent faces of spacedtrunnion brackets 33 secured by machine bolts 39 to" the underside of awork table 43. A tie bolt 4I' extends through the brackets 38 above thegrooves 3l. Arcuate relativev movement of the edges of plate 35 in thegrooves 37 provides in eiect a pivotal connectionY between the table andthe arm 5 about a center 42 lying substantially in the plane of theupper surface of the table. An arm 43 is rigidly secured by screws 44'to one of the brackets 38 and the free end of arm 43 is pivotallyconnected to pivot block 3I.

The length of arm 43 is such that the distance between the center ofpivotal movement of the table relative to arm 5' and the pivotal centerof block 3| is substantially equal to the distance between pivot 33 andthe center of shaft I`9'about which frame 3 pivots. The length of link32 is substantially equal to the distance between the center of shaft I9and the center ofV pivotal movement of the table relative to arm 5.

By this arrangement arm 43 andV link 32' form a toggle and, as screw 29is rotated by hand wheel 30. it is drawn inwardly or outwardly throughthreaded block 2.1, the block 3l moving with it tending to straighten orbreak the toggle and thereby tilt frame 3 and with it the saw band, asshown in Fig. 3. Since table 48 is xed to the toggle arm 43 itv pivotswith it and because of the linkage relationship above described is givena planetary movement about the axis I9, maintaining its horizontalposition throughout the range of tilting movement of the frame and saw.

A further and important advantage of this arrangement lies in thek factthat the lower guide I5 will always remain a xed distance from the table45 and will tilt with the blade 1, thereby removing the necessity formounting said guide in a slide which would tend to collect sawdust andpresent an objectionable maintenance problem.

The table is provided (Fig. 6) with a thin slotted plate 45, theposition of the slot substantially coinciding with the pivot point 42 sothat the slot does not need to be of unusual width to accommodate thetilting movement of the saw.

A- spring 46. having one end adjustably connected to the C-frame at 4'1and pivotally connected` at the other end to the base I by a link 48 isprovided to in part at least counterbalance the tilting C-frame 3. Y

The cover 22, which is fixed to and tilts'with the C-frame, is providedwith an arcuate scale 4 4S concentric with the lower wheel 6. Anindcator 53 is nxed to base I, and when the C-frame is tilted, asdescribed above, the indicator will indicate the degree to which theblade 'I is inclined relative to the table 40.

Preferably means are provided for positively clamping the frame 3 in anyposition of angular adjustment. As shown, such means generally indicatedat 5I comprises (Fig. 7) a pair of opposed wedge blocks 52 and53slidably and nonrotatably mounted in an opening 54 formed in one ofthe pivotal bearing lugs 24, and engaging the xed pivot sleeve 2. Theblocks 52 and 53 areadapted to be drawn into wedging engagement with thesleeve to lock the frame thereto by means of a rod 55, the inner endportion of which is reduced to form a shoulder 56. Block 53 is slidablymounted on the reduced end portion of rod 55 with itsouter end inengagement with shoulder 55, the end of the rod being threaded in block5'2` whereby rotation ofthe rod draws the blocks toward each other andinto clamping engagement withmthe pivot sleeve. The outer end o the rod55 is provided` with a handle 51 for convenience in turning the rod.

The combination of a pivoted saw frame and means to impart a planetarymovement t'o the table as the frameV is tilted, makes possible anextremely simple and economical construction. by which the table ismaintained in a horizontal position throughout the range of angularadjustment of the saw.

While the linkage arrangement above described has certain manufacturingadvantages, it will be understood that other. means maybe employed tosecure the planetary movement of the table about the axis or the sawframe pivot.. For example, a planetary gear transmission may beinsertedbetween the table and pivot.

As shown in Fig. 8,.the xed base. I. is provided with a fixed gearsegment 60 centered at the axis of the pivotal. connection between theC.- frame 3 and base YI. A planetary gear 6I is fixed to a shaft 62,which is journaled in the lower arm 5 of the C-frame, the gear 6I. beingpositioned to engage and travel over thesegment GQ when the C-frame istilted, as shown in phantom lines. The work table 40 has xed thereto agear segment 63 which is centered at the axis 42 about which the tablepivots relative tothe saw frame. The gear 6I engages segment 63l and asthe gear travels over the, segment 60 it imparts a planetary motion tothe; table to maintain the latter horizontal as` the C-frame and saw aretilted about the pivotal connection between the frame and. base. Thetilting. of the frame may he` accomplished by meansv of a handwheel, notshown, secured to the shaftGZ, or. by other .suitable means acting onshaft. 52 or on the frame or table as previously described..

As shown in Fig. 8. the. gear segments 60= and 33 are connected by asingle gear. 6I in which case the segmentsare ofequal radius, but itwillbe understood that segments ofy unequal radius may be used if connectedby. a gear chainy of compensating ratio, the essentialfeature. beingthat the table and frame tilt. in opposite directions through equalangles aboutv their respective pivotal axes.

While the invention hasbeen described in relation to. a two-wheel saw,it is equally applicable to machines having three, or more, bandwheels.

What is claimed is:

1. In a band-saw machine, a base; a frame pivotallyconnected to saidbase, a saw' band' supporting wheel rotatably carried bythe frame, a

second saw band supporting wheel rotatably carried by the base andmounted for rotation about the axis of said, pivotal connection, ahorizontal Work table directly and pivotally connected to said frame`for movement therewith,

the axes of said pivotal connections being paral- 2. In a band-sawmachine, a-base, a frame pivotally connected to said base, a saw bandrsupporting wheel rotatably carried byv the frame, a second saw bandsupporting wheel carried by the base and mounted for rotation about theaxis of said pivotal connection, a horizontal work table carried by theframe and mounted thereon for pivotal movement relative to the frameabout -an`axis parallel to the axis of said pivotal coni nection betweenthe frame and base, and means to simultaneouslyppivot said 'frame Vandtable about their respective pivotal. axes in opposite directionsthrough` equal arcs to maintain the tablefhorizontal throughout ytherange of'pivotalvmovement of the frame and table-about the axis of thepivotal connection `of the frame to thel base.

3. In a band-saw machine, a base, a frame pivotally connected to saidbase, a saw band supporting wheel rotatablycarried by the frame, asecond saw band supporting wheel carried kby the base and mounted forrotation about theaxis 5` vcarried by the frame and mounted forpivotalmovement relative to the. frame about 'an axis yparallel to theaxis of said pivotal connection between the frame land base, -a toggleof which one link is pivoted to thebase at a point spaced from theinst-mentioned axis and the second link is iixed to the table, saidlinks being pivoted together at a point spaced from the second axis,said spacings being substantially equal, ythe length orsaid first linkbeing sublstantially equal to the distance between said axes, and meansoperable on said iirst toggle `link to swing the same about the point atwhich it is pivoted to the base to Atilt said frame around said l secondsaw band supporting wheel carried by of said pivotal connectionyaworktableA carried Y by the frame and mounted `for pivotal movement relativeto the framev about an axis parallel to the axis of said pivotalconnection between the frame and base, a link, one end of which ispivotally connected to the base at a point spaced from thefirst-mentioned axis, the other end of said link being pivoted to thetable at a 'point spaced from vthe secondV axis, said spacings beingsubstantiallyA equal, the length of said link lbeingsubstantially equalto the distance between said axes, and means to -tiltuithethe'iirst-mentioned axis." l

4. In a band-saw machine, a base, a frame pivotally connected to saidbase, a saw band supporting wheel rotatably carried by the frame, asecond saw. band supporting wheel' carried by the base and mounted forrotation about the axis of said pivotal connection, a work table carriedby the frame and mounted for pivotal movement relative to theframe aboutan axis parallel to the axis of said pivotal connection between theframe and base and lying substantially in the plane of the tablesurface, a toggle of which one link is pivoted to the base at a pointspaced from vframe around the rst-inentioned axis andthe second link is.

xed to the table, said links being pivotally connected at a, pointspaced from the second axis. said spacings beingsubstantially equal, thelength of said first link being substantially equal .to the distancebetween said axes, and means operable on one of the links of said toggleto make and breakA the toggle to Ytilt the frame around thefirst-mentioned axis.

5. In a band-saw machine, a base, a frame pivotally connected to saidbase, a saw band supporting wheel rotatably carried by the frame, asecond saw band supporting wheel carried by the base and mountedforrotation about the axis of saidv pivotal connection, a ywork tablethe base and mounted for rotation about the axis of saidpivotalconnection, a.A work table carried by the frame and mounted forpivotal movementk relative to the frame about an axis parallel to theaxis of said pivotal connection between the framev and base, a toggle ofwhich one link is pivoted to the base at a point spaced from thefirst-mentioned axis and the second link is xed to the table, saidlinksbeing pivoted together at a point spaced from the second axis, saidspacings being substantially equal, the length of said first link beingsubstantially equal to the distance between said axesand means acting onthe knee of the toggle to make and break the same, to tilt said framearound said rstmentioned axis, said means including a jack screwpivotallysupported at the knee of said toggle land engaged in a threadedblock pivoted to said ase.

7. In a band-vsawmachine, a base, a C-iramel pivotally connected to saidbase, said C-frame having spaced upper and lower arms, a saw bandsupporting wheel rotatably carried by the upper arm of the C-frame, asecond saw band supporting Wheel carried Vby the base mounted forrotation about the axis of said pivotal connection, a work table, thefree end of the lower armof said C-frame and the underside of the tablebeing provided with interengaging connecting members, one of saidmembers being provided with arcuate grooves and the other member beingprovided with arcuate iianges slidably engaging in said grooves topermit pivotal movement of the table relative to the C-frame about anaxis parallel to the axis of said pivotal connection between the C-frameand base, a link, one end of which is pivotally connected to the base ata point spaced from the first-mentioned axis, the other end of said linkbeing pivoted to the table at a point spaced from the second axis,saidspacings being substantially equal, the length of said link beingsubstantially equal tothe distance between said axes, means to tilt theC-frame around the rstmentioned axis,and means to clamp the C-frame inany selected tilted position.

8. In a band-saw machine, a base, a C-frame pivotally connected to saidbase, said C-frame having spaced upper and lower arms, a saw bandsupporting wheel rotatably carried by the upper arm of the C-frame, asecond saw band supporting wheel carried by the base and mounted forrotation about the axis of said pivotal connection,

the free end of the lower arm of said C-frame 1 being formed with anarcuate cradle opening toward the upper C-frame arm, a work table havingarpairxof spaced parallel trunnion brackets rigidly .secured to theundersidey thereof, the adjacent faces of said brackets lbeing providedAwitharcuate grooves concentric with said cradle, an. arcuate plateconcentric with and secured in said cradle, the edges of Vsaid platesldably engaging in said grooves for pivotal movement. of the tablerelaf4 tivev to the'` C-frame about an axis parallel to the axis of saidpivotal connection betweenthe C.frame and the base, a link, oneend ofwhich is pivotally connected to the base` atl a. point spaced from thefirst-mentioned ax-is, thevother end of said link being pivoted to thetable at a point spaced from the second axis, said-spacings beingsubstantially equal, the length of said link being; substantially equaltothe distance. between said axes, and means to tilt the C-frame aroundthe first-mentioned axis.

9. In a band-saw machine, a. base, a. frame pivotally connected to saidbase, a. saw band supporting wheel. rotatably carried by the frame, asecond saw band supporting Wheel carried by the base and mounted forrotation about the axis of said pivotal connection, a Work table carriedby the frame and mounted for pivotal movement relative to the frameabout an axis parallel to the axis of said pivotal connection betweenthe frameV and base and lying substantially in the plane of thetablesurface, a toggle of which one linkis pivoted to the base at apoint spaced from the rst-mentioned axis and the second link is iixed tothe table, said links being pivotally connected at a point spaced fromthe second axis, said spacings being substantially equal, the length ofsaid first link being substantially equal tothe distance between saidaxes, meansl operable on one of the links of said toggle to make andbreak the toggle totilt the frame around the first-mentioned axis, and aspring adjustably connected at one end to the frame and pivotallyconnected at the other end of the base to at least partiallycounterbalance the tilting frame.

10. In a band-saw machine, a base, a frame pivotally connected to saidbase, a saw band supporting` wheel rotatably carried by the frame, asecond saw band supporting wheel rotatably carried by the base andmounted for rotation about; the axis-ofjsaid'pivotalconnection, ahorizontal worktable carried byr the frame and mounted thereon; for;pivotal movement relative thereto about an axis parallel to the axis ofsaid pivotal-connection of the frame to the base, and a gear trainbetween table and base to simultaneously pivot said frame and tableabout their respective pivotalV axes in opposite directions throughequaly arcs to maintain the table horizontalv throughout the range ofpivotal movement of the frame and table about the axis of the pivotalconnection of the frame to the base, said gear trainV` including a gearmember fixed to the base and a s econdgear member'xed to the table.

l theirameandmounted thereon for pivotalV movementfrelative to the frameabout an axis parallel to the axis of said pivotal connection betweentheframe, and base, a segmental gear xed to the base and centered attheaxis of the pivotal Y connection between the frame and base, a secondsegmental gear xed to the table and centered at the axis of* the pivotalconnection between the table and frame, and a gear rotatably mounted``in said frame and meshing with both said gear segments, saidsegmentsbeing of equal

